1. Field
The following description relates to a polyphosphonate, a lens including polyphosphonate, a camera module using the polyphosphonate lens, and the method of preparing the polyphosphonate and the lens.
2. Description of Related Art
In various optical systems of cameras, optical glasses or transparent resins for optical applications are used as materials to produce optical elements.
An optical glass exhibits good heat resistance, transparency, dimensional stability, chemical resistance and the like, producing a lens that is stable in dimension. Various other materials with different refractive indexes (nD) or Abbe's numbers (υD) are commercially available and have been considered as a possible material for producing optical elements. However, many of these materials tend to be expensive and have poor moldability and low productivity. With some materials, high-tech processes are necessary to shape the materials into aspherical lenses that may be used for aberration correction in cameras, thus, increasing the manufacturing cost.
The use of a transparent resin for optical applications for camera lenses and the like is described in KR Patent Publication No 2003-0085020, which discloses transparent molded objects, optical member, and plastic lens, as well as process for producing these objects.